US4630059A - Four-port network coupling arrangement for microwave antennas employing monopulse tracking - Google Patents

Four-port network coupling arrangement for microwave antennas employing monopulse tracking Download PDF

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Publication number
US4630059A
US4630059A US06/620,491 US62049184A US4630059A US 4630059 A US4630059 A US 4630059A US 62049184 A US62049184 A US 62049184A US 4630059 A US4630059 A US 4630059A
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Prior art keywords
waveguide
hybrid
arms
feed horn
signals
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Expired - Fee Related
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US06/620,491
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English (en)
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Gunter Morz
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Bosch Telecom GmbH
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ANT Nachrichtentechnik GmbH
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q25/00—Antennas or antenna systems providing at least two radiating patterns
    • H01Q25/04—Multimode antennas
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/16—Auxiliary devices for mode selection, e.g. mode suppression or mode promotion; for mode conversion

Definitions

  • the present invention relates to a four-port network for the separation of four signal paths associated with two polarizations in each of two frequency bands, whose input waveguide, in which the signals of both frequency bands and both polarizations are able to propagate, is connected with the feed horn of a microwave antenna, and which is provided with a circuit branching arrangement for separating the frequencies and polarizations. More particularly the present invention relates to an improved arrangement for coupling the four-port network to the microwave antenna feed horn in a system wherein the antenna is provided with a monopulse tracking system for the antenna.
  • Microwave antennas are frequently utilized to transmit and receive signals from two frequency bands and two polarizations. Feeder systems permitting such multiple utilization of the antenna are known by the name of four-port network, system filter or quadruplexer.
  • the state of the art includes four-port networks designed for two linearly orthogonally polarized frequency bands (see, for example, Federal Republic of Germany DE-AS No. 2,443,166 and corresponding U.S. Pat. No. 3,978,434), and those designed for two circularly orthogonally polarized frequency bands (see, for example, DE-OS No. 2,932,626 and corresponding U.S. Pat. No. 4,344,048, and DE-OS No. 2,703,878 and corresponding U.S. Pat. No. 4,319,206).
  • Such four-port networks are used, for example, in ground station antenna for satellite radio operating in the 4/6 GHz range.
  • methods and apparatus are required which permit tracking of the ground station antenna with the associated satellite.
  • This is done with the aid of the known monopulse method according to which antenna deviation signals are derived from the radiation characteristics of one or a plurality of higher order waveguide modes.
  • monopulse methods are described in great detail in, for example, German Pat. No. 2,135,611 and corresponding U.S. Pat. No. 3,758,880 and in German Pat. No. 2,212,996 and corresponding U.S. Pat. No. 3,864,683.
  • the frequency band (4 GHz) of the downward or received signal generally lies far below the frequency band (6 GHz) of the upward or transmitted signal.
  • the monopulse device of the ground station antenna needs the downward signal (received signal) to derive the deviation signals.
  • mode couplers Devices for coupling the higher order modes into a waveguide and particularly into a conical antenna feed horn are known as mode couplers, e.g. see German Pat. No. 2,135,611 and corresponding U.S. Pat. No. 3,758,880, German Pat. No. 2,212,996 and corresponding U.S. Pat. No. 3,864,683, DE-AS No. 2,460,552 and corresponding U.S. Pat. No. 3,964,070, and German Pat. No. 2,608,092 and corresponding U.S. Pat. No. 4,048,592. These publications show that the mode couplers are rather costly structures.
  • a longitudinally arranged conductor is disposed along the longitudinal axis of the waveguide connecting the antenna feed horn and the four-port network, with this conductor extending from the region of the throat of the antenna feed horn, where it couples in at least the signals of one higher order mode which are able to propagate there to the vicinity of the branching arrangement in the input waveguide of the four-port network so that the higher order mode signals traveling along the conductor are coupled, together with the communication signal of one frequency band, to the arms of the branching arrangement and the higher order mode signals are separated from the communication signals by means of hybrids which connect the branching arms associated with one polarization.
  • FIG. 1 is a longitudinal sectional view of a four-port network, or system filter, connected to a grooved or corrugated antenna feedhorn via a coupling arrangement according to the invention.
  • FIG. 2 shows a cross sectional view of a waveguide in which a conductor is fastened by dielectric filaments.
  • FIG. 3 shows a cross sectional view of a polarization converter in which a conductor is supported.
  • FIG. 1 there is shown a longitudinal sectional view of a grooved antenna feed horn 1 which is connected to a four-port network 2.
  • the four-port network is disclosed in detail in, for example, Federal Republic of Germany DE-AS No. 2,443,166 and corresponding U.S. Pat. No. 3,978,434, issued Aug. 31, 1976.
  • this four-port network 2 begins with an input waveguide 3 having a circular or square cross section wherein two doubly polarized waveguide modes can propagate in two frequency bands, e.g., 4 GHz and 6 GHz.
  • the input waveguide 3 is followed by a waveguide section 4 having a tapering cross section which forms the transition to a waveguide 5 in which, due to its cross-sectional dimensions, the waves of the lower frequency band (4 GHz) are unable to propagate.
  • Waveguide 5 is followed by a polarization filter (not shown in this figure) which divides the waves of the upper frequency band (6 GHz) into its two orthogonal polarizations.
  • FIG. 1 shows only those coupling elements 6, 7 which lie in a longitudinal plane.
  • the other two coupling elements are arranged in the longitudinal sectional plane perpendicular to the plane of the drawing.
  • Each one of the two coupling elements 6 and 7 is connected to a respective waveguide arm 8, 9 each having integrated therein a respective filter 10,11 which, for example, are in the form of coaxial bandfilters.
  • filters 10,11 serve to block upper frequency band signal components which have been coupled in by coupling elements 6, 7 together with the signals of the lower frequency band.
  • the other two coupling elements are each similarly connected to a respective waveguide arm including a respective filter which functions in the same manner as the filters 10 and 11.
  • the communication signal of the lower frequency band of the one polarization direction is then present at the sum output 13 of the hybrid 12 while the communication signal of the lower frequency band of the other polarization direction is then present at the sum output of the second hybrid (not shown).
  • the above-described four-port network 2 which is based, as indicated above, on DE-AS No. 2,443,166 and U.S. Pat. No. 3,978,434, is designed to separate linearly polarized signals from two different frequency bands.
  • the four-port network By simply supplementing the four-port network, in the manner disclosed in DE-OS No. 2,932,626, corresponding to U.S. Pat. No. 4,344,048, with one polarization converter placed upstream of the input waveguide section 3 and a second polarization converter between waveguide 5 and the polarization filter (not shown) for the upper frequency band, the four-port network is also able to separate circularly polarized signals.
  • FIG. 1 shows the means with which the higher order E 01 mode or E 11 mode, which customarily are unable to propagate through the throat of the antenna feed horn 1 and then through the subsequent input waveguide (which in the illustrated embodiment includes waveguide sections 14 and 15 in addition to section 3) due to its cross-sectional dimensions, is coupled to the four-port network 2.
  • the coupling is effected by means of a conductor 16 which is disposed along the longitudinal axis of the input waveguide 14, 15, 3, and passes centrally through waveguide sections 14, 15, 3 between antenna feed horn 1 and the branches for the frequency bands in four-port network 2.
  • Waveguide section 14 here represents a transition from a circular waveguide cross section, for example of the feedhorn 1, to a square waveguide cross section e.g. of the waveguide section 3, (or vice versa), and waveguide section 15 is, for example, a polarization converter as known from DE-OS No. 2,932,626 and corresponding U.S. Pat. No. 4,344,048.
  • Conductor 16 extends into antenna feed horn 1 (which in the illustrated embodiment has a circular cross section) so that it completely couples in the higher order mode which is present if there is an antenna deviation (i.e., the E 01 mode in a grooved antenna feed horn with a circular cross section) and converts this higher order mode into a coaxial mode (TEM mode).
  • antenna deviation i.e., the E 01 mode in a grooved antenna feed horn with a circular cross section
  • TEM mode coaxial mode
  • conductor 16 ends and generates an aperiodic E 11 field which is coupled, together with the communication signal of the lower frequency band, to the waveguide arms 8, 9 following behind the coupling means 6 and 7.
  • the higher order mode is finally separated from the communication signal mode in the 180° hybrid 12 which brings together waveguide arms 8, 9. In this way, the communication signal can be obtained at the sum output 13 and the signals of the higher order mode at the difference output 17 of hybrid 12.
  • the four-port network 2 is equipped with a total of two hybrids, each of which brings together two waveguide arms. At its difference output, each hybrid thus furnishes a signal component of the higher order mode.
  • Both higher order mode signal components can be combined, for example, in that the difference outputs of the two hybrids are connected together by means of a 3dB coupler and a preconnected phase shifting member.
  • one of the two difference outputs may be provided with a displaceable short-circuit so that impedence matching of the other difference output with the higher order mode can be optimized at a desired frequency.
  • FIG. 2 depicts a cross sectional view of the waveguide 15 equipped with the above mentioned dielectric support. This support has four dielectric arms 18, 19, 20 and 21 which end in the four corners of the waveguide 15 and surround the conductor 16 in the center of the waveguide.
  • waveguide section 15 is designed as a polarization converter as disclosed in DE-OS No. 2,932,626 and U.S. Pat. No. 4,344,048, the conductor 16 may be fastened to the diagonally extending dielectric plate.
  • FIG. 3 shows a cross sectional view of the waveguide section 15 designed as a polarization converter.
  • the diagonally extending dielectric plate is divided into two plate sections 22 and 23 between which the conductor 16 is placed. These two plate sections 22 and 23 and the conductor 16 are embedded by two additional dielectric plates 24 and 25.

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  • Waveguide Aerials (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Waveguide Switches, Polarizers, And Phase Shifters (AREA)
US06/620,491 1983-06-18 1984-06-14 Four-port network coupling arrangement for microwave antennas employing monopulse tracking Expired - Fee Related US4630059A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP83105973.8 1983-06-18
EP83105973A EP0128970B1 (de) 1983-06-18 1983-06-18 Viertornetzwerk für Mikrowellenantennen mit Monopulsnachführung

Publications (1)

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US4630059A true US4630059A (en) 1986-12-16

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US06/620,491 Expired - Fee Related US4630059A (en) 1983-06-18 1984-06-14 Four-port network coupling arrangement for microwave antennas employing monopulse tracking

Country Status (6)

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US (1) US4630059A (enrdf_load_stackoverflow)
EP (1) EP0128970B1 (enrdf_load_stackoverflow)
JP (1) JPS6014502A (enrdf_load_stackoverflow)
BR (1) BR8402898A (enrdf_load_stackoverflow)
CA (1) CA1221163A (enrdf_load_stackoverflow)
DE (1) DE3381303D1 (enrdf_load_stackoverflow)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4785306A (en) * 1986-01-17 1988-11-15 General Instrument Corporation Dual frequency feed satellite antenna horn
US4849761A (en) * 1988-05-23 1989-07-18 Datron Systems Inc. Multi-mode feed system for a monopulse antenna
US4920351A (en) * 1986-03-24 1990-04-24 Computer Science Inovations, Inc. Diplexer for orthogonally polarized transmit/receive signalling on common frequency
US5258768A (en) * 1990-07-26 1993-11-02 Space Systems/Loral, Inc. Dual band frequency reuse antenna
US5471223A (en) * 1993-12-01 1995-11-28 The United States Of America As Represented By The Secretary Of The Army Low VSWR high efficiency UWB antenna
US6529098B2 (en) * 2000-03-01 2003-03-04 Prodelin Corporation Transmitting and receiving apparatus for satellite communication via dual-polarized signals
US20050116871A1 (en) * 2003-09-25 2005-06-02 Prodelin Corporation Feed assembly for multi-beam antenna with non-circular reflector, and such an assembly that is field-switchable between linear and circular polarization modes
US20070202022A1 (en) * 2006-02-24 2007-08-30 Sang Baek Shin Annular distributor having guide vane to improve flow rate distribution
DE102013011651A1 (de) 2013-07-11 2015-01-15 ESA-microwave service GmbH Antennen-Speisesystem im Mikrowellenbereich für Reflektorantennen
US12085758B1 (en) * 2022-04-29 2024-09-10 Lockheed Martin Corporation Twist feed radio frequency polarizer

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5109232A (en) * 1990-02-20 1992-04-28 Andrew Corporation Dual frequency antenna feed with apertured channel
JP4965880B2 (ja) * 2006-03-30 2012-07-04 富士通コンポーネント株式会社 アンテナ装置
DE102020129465A1 (de) 2020-10-05 2022-04-07 Hiltron GmbH Satellitenantennensystem

Citations (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2207845A (en) * 1938-05-28 1940-07-16 Rca Corp Propagation of waves in a wave guide
DE750823C (de) * 1941-12-05 1945-01-27 Hohlrohrleitung zur dielektrischen Fortleitung kurzer elektrischer Wellen
US2709240A (en) * 1954-02-02 1955-05-24 Rca Corp Multi-mode waveguide system
DE1942678A1 (de) * 1968-08-21 1970-05-21 Rca Corp Anordnung zur Signalspeisung bei einer in mehreren Modes arbeitenden Einzelimpulsanlage
US3573838A (en) * 1968-10-28 1971-04-06 Hughes Aircraft Co Broadband multimode horn antenna
FR2096860A1 (enrdf_load_stackoverflow) * 1970-07-07 1972-03-03 Radiotechnique Compelec
US3665481A (en) * 1970-05-12 1972-05-23 Nasa Multi-purpose antenna employing dish reflector with plural coaxial horn feeds
US3758880A (en) * 1971-07-16 1973-09-11 Licentia Gmbh Waveguide mode coupler for separating waves of useful mode from waves of higher mode
DE2212996A1 (de) * 1972-03-17 1973-09-27 Licentia Gmbh Anordnung eines eigennachfuehrsystems fuer mikrowellenantennen
US3815136A (en) * 1972-09-11 1974-06-04 Philco Ford Corp Coaxial tracking signal coupler for antenna feed horn
DE2460552A1 (de) * 1973-12-20 1975-07-03 Thomson Csf Hornstrahler mit anordnung zur entnahme von der ablagemessung dienenden wellentypen
DE2443166A1 (de) * 1974-09-10 1976-03-25 Licentia Gmbh Systemweiche zur trennung zweier signale, die aus je zwei doppelt polarisierten frequenzbaendern bestehen
DE2608092A1 (de) * 1975-02-28 1976-09-09 Thomson Csf Vorrichtung zur entnahme von wellentypen bestimmter fuer ablagemessungen geeigneter ordnung aus einem nutenhohlleiter
DE2521956A1 (de) * 1975-05-16 1976-11-18 Siemens Ag Polarisationsweiche
DE2703878A1 (de) * 1977-01-31 1978-08-03 Siemens Ag Polarisationsweiche
DE2737125A1 (de) * 1977-08-17 1979-02-22 Spinner Gmbh Elektrotech Uebertragungsleitungssystem
DE2804132A1 (de) * 1978-01-31 1979-08-02 Siemens Ag Wellentypenweiche
US4241353A (en) * 1978-02-24 1980-12-23 Thomson-Csf Multimode monopulse feed and antenna incorporating same
DE2932626A1 (de) * 1979-08-11 1981-02-12 Licentia Gmbh Viertornetzwerk zur trennung zweier aus doppelt polarisierten frequenzbaendern bestehenden signalen
US4268804A (en) * 1977-08-17 1981-05-19 Spinner Gmbh Transmission line apparatus for dominant TE11 waves
EP0041077A2 (de) * 1980-05-30 1981-12-09 ANT Nachrichtentechnik GmbH Antennenspeisesystem für eine nachführbare Antenne
US4344048A (en) * 1979-08-11 1982-08-10 Licentia Patent-Verwaltungs-G.M.B.H Four-port network for separating two signals comprised of doubly polarized frequency bands

Patent Citations (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2207845A (en) * 1938-05-28 1940-07-16 Rca Corp Propagation of waves in a wave guide
DE750823C (de) * 1941-12-05 1945-01-27 Hohlrohrleitung zur dielektrischen Fortleitung kurzer elektrischer Wellen
US2709240A (en) * 1954-02-02 1955-05-24 Rca Corp Multi-mode waveguide system
DE1942678A1 (de) * 1968-08-21 1970-05-21 Rca Corp Anordnung zur Signalspeisung bei einer in mehreren Modes arbeitenden Einzelimpulsanlage
US3573838A (en) * 1968-10-28 1971-04-06 Hughes Aircraft Co Broadband multimode horn antenna
US3665481A (en) * 1970-05-12 1972-05-23 Nasa Multi-purpose antenna employing dish reflector with plural coaxial horn feeds
FR2096860A1 (enrdf_load_stackoverflow) * 1970-07-07 1972-03-03 Radiotechnique Compelec
US3758880A (en) * 1971-07-16 1973-09-11 Licentia Gmbh Waveguide mode coupler for separating waves of useful mode from waves of higher mode
DE2212996A1 (de) * 1972-03-17 1973-09-27 Licentia Gmbh Anordnung eines eigennachfuehrsystems fuer mikrowellenantennen
US3864683A (en) * 1972-03-17 1975-02-04 Licentia Gmbh Arrangement for an automatic resetting system for microwave antennas
US3815136A (en) * 1972-09-11 1974-06-04 Philco Ford Corp Coaxial tracking signal coupler for antenna feed horn
DE2460552A1 (de) * 1973-12-20 1975-07-03 Thomson Csf Hornstrahler mit anordnung zur entnahme von der ablagemessung dienenden wellentypen
DE2443166A1 (de) * 1974-09-10 1976-03-25 Licentia Gmbh Systemweiche zur trennung zweier signale, die aus je zwei doppelt polarisierten frequenzbaendern bestehen
US3978434A (en) * 1974-09-10 1976-08-31 Licentia Patent-Verwaltungs-G.M.B.H. System separating filter for separating first and second doubly polarized frequency bands
DE2608092A1 (de) * 1975-02-28 1976-09-09 Thomson Csf Vorrichtung zur entnahme von wellentypen bestimmter fuer ablagemessungen geeigneter ordnung aus einem nutenhohlleiter
DE2521956A1 (de) * 1975-05-16 1976-11-18 Siemens Ag Polarisationsweiche
DE2703878A1 (de) * 1977-01-31 1978-08-03 Siemens Ag Polarisationsweiche
DE2737125A1 (de) * 1977-08-17 1979-02-22 Spinner Gmbh Elektrotech Uebertragungsleitungssystem
US4268804A (en) * 1977-08-17 1981-05-19 Spinner Gmbh Transmission line apparatus for dominant TE11 waves
DE2804132A1 (de) * 1978-01-31 1979-08-02 Siemens Ag Wellentypenweiche
US4241353A (en) * 1978-02-24 1980-12-23 Thomson-Csf Multimode monopulse feed and antenna incorporating same
DE2932626A1 (de) * 1979-08-11 1981-02-12 Licentia Gmbh Viertornetzwerk zur trennung zweier aus doppelt polarisierten frequenzbaendern bestehenden signalen
US4344048A (en) * 1979-08-11 1982-08-10 Licentia Patent-Verwaltungs-G.M.B.H Four-port network for separating two signals comprised of doubly polarized frequency bands
EP0041077A2 (de) * 1980-05-30 1981-12-09 ANT Nachrichtentechnik GmbH Antennenspeisesystem für eine nachführbare Antenne

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4785306A (en) * 1986-01-17 1988-11-15 General Instrument Corporation Dual frequency feed satellite antenna horn
US4920351A (en) * 1986-03-24 1990-04-24 Computer Science Inovations, Inc. Diplexer for orthogonally polarized transmit/receive signalling on common frequency
US4849761A (en) * 1988-05-23 1989-07-18 Datron Systems Inc. Multi-mode feed system for a monopulse antenna
US5258768A (en) * 1990-07-26 1993-11-02 Space Systems/Loral, Inc. Dual band frequency reuse antenna
US5471223A (en) * 1993-12-01 1995-11-28 The United States Of America As Represented By The Secretary Of The Army Low VSWR high efficiency UWB antenna
US6529098B2 (en) * 2000-03-01 2003-03-04 Prodelin Corporation Transmitting and receiving apparatus for satellite communication via dual-polarized signals
US20050116871A1 (en) * 2003-09-25 2005-06-02 Prodelin Corporation Feed assembly for multi-beam antenna with non-circular reflector, and such an assembly that is field-switchable between linear and circular polarization modes
US7236681B2 (en) 2003-09-25 2007-06-26 Prodelin Corporation Feed assembly for multi-beam antenna with non-circular reflector, and such an assembly that is field-switchable between linear and circular polarization modes
US20070202022A1 (en) * 2006-02-24 2007-08-30 Sang Baek Shin Annular distributor having guide vane to improve flow rate distribution
DE102013011651A1 (de) 2013-07-11 2015-01-15 ESA-microwave service GmbH Antennen-Speisesystem im Mikrowellenbereich für Reflektorantennen
US12085758B1 (en) * 2022-04-29 2024-09-10 Lockheed Martin Corporation Twist feed radio frequency polarizer

Also Published As

Publication number Publication date
EP0128970B1 (de) 1990-03-07
JPS6014502A (ja) 1985-01-25
CA1221163A (en) 1987-04-28
JPH0441521B2 (enrdf_load_stackoverflow) 1992-07-08
BR8402898A (pt) 1985-05-21
EP0128970A1 (de) 1984-12-27
DE3381303D1 (de) 1990-04-12

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